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Project: Vcr 2.9.3

Dynamic ERB cassettes

By default, cassettes are static: the exact response that was received
when the cassette was recorded will be replayed for all future requests.
Usually, this is fine, but in some cases you need something more dynamic.
You can use ERB for this.

To enable ERB evaluation of a cassette, pass the :erb => true option
to a cassette. If you want to pass variables to the cassette, you can
pass the names and values of the variables in a hash (:erb => { ... }).

Scenarios
Enable dynamic ERB cassette evalutation using :erb => true
Given
a previously recorded cassette file "cassettes/dynamic.yml" with:
---
http_interactions:
- request:
    method: get
    uri: http://example.com/foo?a=<%= 'b' * 3 %>
    body:
      encoding: UTF-8
      string: ''
    headers: {}
  response:
    status:
      code: 200
      message: OK
    headers:
      Content-Type:
      - text/html;charset=utf-8
      Content-Length:
      - '9'
    body:
      encoding: UTF-8
      string: Hello <%= 'bar'.next %>
    http_version: '1.1'
  recorded_at: Tue, 01 Nov 2011 04:58:44 GMT
recorded_with: VCR 2.0.0
And
a file named "dynamic_erb_example.rb" with:
require 'vcr'

VCR.configure do |c|
  c.hook_into :webmock
  c.cassette_library_dir = 'cassettes'
end

VCR.use_cassette('dynamic', :erb => true) do
  response = Net::HTTP.get_response('example.com', '/foo?a=bbb')
  puts "Response: #{response.body}"
end
When
I run ruby dynamic_erb_example.rb
Then
it should pass with "Response: Hello bas"
Pass arguments to the ERB using :erb => { ... }
Given
a previously recorded cassette file "cassettes/dynamic.yml" with:
---
http_interactions:
- request:
    method: get
    uri: http://example.com/foo?a=<%= arg1 %>
    body:
      encoding: UTF-8
      string: ''
    headers: {}
  response:
    status:
      code: 200
      message: OK
    headers:
      Content-Type:
      - text/html;charset=utf-8
      Content-Length:
      - '9'
    body:
      encoding: UTF-8
      string: Hello <%= arg2 %>
    http_version: '1.1'
  recorded_at: Tue, 01 Nov 2011 04:58:44 GMT
recorded_with: VCR 2.0.0
And
a file named "dynamic_erb_example.rb" with:
require 'vcr'

VCR.configure do |c|
  c.hook_into :webmock
  c.cassette_library_dir = 'cassettes'
end

VCR.use_cassette('dynamic', :erb => { :arg1 => 7, :arg2 => 'baz' }) do
  response = Net::HTTP.get_response('example.com', '/foo?a=7')
  puts "Response: #{response.body}"
end
When
I run ruby dynamic_erb_example.rb
Then
it should pass with "Response: Hello baz"

Last published almost 5 years ago by myronmarston.